#define _CRT_SECURE_NO_WARNINGS 1

#include<stdio.h>
#include<stdbool.h>
struct TreeNode {
    int val;
    struct TreeNode* left;
    struct TreeNode* right;
};
 


bool isUnivalTree(struct TreeNode* root) {
    if (root == NULL)
    {
        return true;
    }
    if (root->left != NULL && root->left->val != root->val)
    {
        return false;
    }
    if (root->right != NULL && root->right->val != root->val)
    {
        return false;
    }
    return isUnivalTree(root->left) && isUnivalTree(root->right);
}
/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     struct TreeNode *left;
 *     struct TreeNode *right;
 * };
 */


int maxDepth(struct TreeNode* root) {
    if (root == NULL)
    {
        return 0;
    }
    int left = 1 + maxDepth(root->left);
    int right = 1 + maxDepth(root->right);
    int dep = left > right ? left : right;
    return dep;
}

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     struct TreeNode *left;
 *     struct TreeNode *right;
 * };
 */


struct TreeNode* invertTree(struct TreeNode* root) {
    if (root == NULL)
    {
        return root;
    }
    struct TreeNode* tmp = root->left;
    root->left = root->right;
    root->right = tmp;
    invertTree(root->left);
    invertTree(root->right);
    return root;
}
/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     struct TreeNode *left;
 *     struct TreeNode *right;
 * };
 */


bool isSameTree(struct TreeNode* p, struct TreeNode* q) {
    if (p == NULL && q == NULL)
    {
        return true;
    }
    if (p == NULL || q == NULL)
    {
        return false;
    }
    if (p->val != q->val)
    {
        return false;
    }
    return isSameTree(p->left, q->left) && isSameTree(p->right, q->right);
}